Primary in vitro stimulation of antibody production by lizard splenocytes

Establishment and characterization of rough-tailed gecko original tail cells

Some of lizard species have the ability to lose their tail in order to defend against predators and regenerate the new tail. Lizard's regenerated tail has attracted scientists' attention for unraveling the regeneration process, but less information is known about the cellular characterization and cell growth properties of original tail. This research aimed to report cell culture and banking process of rough-tailed gecko or Cyrtopodion scabrum's original tail cell sample from inner tissue without skin using tissue explant technique. For banking reports, it is essential to analyze this cells' potential to proliferate, to investigate biological aspects such as cell culture features, differentiation and chromosome number and to report its species identification and quality control. To achieve optimal growth conditions, three different temperatures for incubation including 18, 23 and 37 °C and two different media including DMEM and L-15 were applied. The expanded cells were studied for their potential to adipose and osteoblast differentiation. Results indicated that lizard's original tail cells could be successfully obtained by explant technique. The cells demonstrated fibroblast like morphology with population doubling times of approximately 24 ± 0.5 h. Karyotyping analysis showed a distribution of 2n = 40 chromosome number for this cell line. The comparison of different incubation media and temperatures showed that cell growth is equally optimal in all mentioned conditions according to growth curves. Adipose and osteoblast differentiation was obviously observed in these cells which confirms the hint of stem-ness in the produced mixed cells. According to cell banking policies, produced cells were also checked for bacterial, fungal, yeast and mycoplasma contaminations and no contamination was observed. Multiplex PCR for identification of species confirmed the species of lizard with no cross-contamination with other cells in the cell bank. Establishment of authenticated and well-characterized lizard's original tail cell line will provide a valuable source for subsequent in vitro regenerative research and molecular studies which are not feasible in in vivo methods. This finding will allow us to get an opportunity to create and preserve a new collection of lizard cell lines in the future.

Review: 2-mercaptoethanol alteration of in vitro immune functions of species other than murine

Descriptions that organosulfurs could alter biologically relevant cellular functions began some 40 years ago when cell mediated and humoral murine in vitro immune responses were reported to be dramatically enhanced by any of four xenobiotic, sulfhydryl compounds—2-mercaptoethanol (2-ME), dithiothreitol, glutathione, and l-cysteine; the most effective of the four was 2-ME. These findings triggered a plethora of reports defining 2-ME benefits for a multitude of immunological processes, primarily with murine models. This led to investigations on 2-ME alterations of (a) immune functions in other species, (b) activities of other cell-types, and (c) in situ diseases. In addition, the early findings may have been instrumental in the identification of the previously undefined anticarcinogenic chemicals in specific foods as organosulfurs. Outside the plant organosulfurs, there are no comprehensive reviews of these areas to help define mechanisms by which organosulfurs function as well as identify potential alternative uses. Therefore, the present review will focus on 2-ME alterations of in vitro immune functions in species other than murine; namely, fish, amphibian, reptile, avian, whales, dolphins, rat, hamster, rabbit, guinea pig, feline, canine, porcine, ovine, bovine, and human. Processes, some unique to a given species, were in general, enhanced and in some cases dependent upon the presence of 2-ME. The largest benefits occurred in media that were serum free, followed by those in autologous serum and then fetal bovine serum supplemented medium. Concentrations of 2-ME were generally in the low μM range, with exceptions of those for salamander (20 mM), turtles (70 mM) and dolphins (7 mM). The few studies designed to assess mechanisms found that changes induced by 2-ME were generally accompanied by alterations of reduced/oxidized glutathione cellular concentrations. The major benefit for most studies, however, was to increase the sensitivity of the culture environment, which permitted a specific process to be more easily dissected.

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2-ME altered in vitro immune functions of species other than murine.

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Benefits were found for species from fish to humans.

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Enhancement occurred in serum-free and in autologous or fetal bovine serum.

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Generally, optimal concentrations of 2-ME were in the low uM range.

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Concentration exceptions were salamander (20 mM), turtles (70 mM), and dolphins (7 mM).

Endogenous corticosteroids mediate seasonal cyclic changes in immunity of lizards

Endogenous corticosteroid (CS) blood levels were radioimmunoassayed in fresh, field-collected lizards Chalcides ocellatus at two week-intervals throughout the four consecutive seasons. These animals were used in parallel to investigate the splenic T and B lymphocyte level, lymphoproliferative responsiveness to concanavalin A and primary antibody production in vitro against rat erythrocytes (RRBC). The recorded data indicated that fully developed splenic lymphoid tissue and powerful immune responsiveness are coincident with a continuously low CS level, and characterize the period from spring through early autumn. On the other hand, the dramatic lymphocytic destruction and impairment of immune reactivity observed in autumn and winter are associated with not only a high, but above all sustained, rise in endogenous CS levels. Apparently, exposure of lizard lymphocytes to comparatively high, yet physiologic, levels of endogenous CS for prolonged periods of time lead to impairment of their immune functions. In support, long-term administration of exogenous hydrocortisone acetate (HC) to "summer" lizards resulted in a high and lasting elevation in blood CS levels that was associated with a considerable depletion of lymphoid elements and abrogation of immune reactivity, exactly as in normal lizards collected from the field in autumn through winter. In addition, pharmacologic inhibition of CS synthesis by administration of metyrapone at the beginning of autumn greatly modulated the lizard lymphocyte response to the autumn-related immunodepression. The study thus strongly suggests that the autumn/winter-dependent immunosuppression in lizards is essentially due to a high and lasting rise in levels of endogenous CS. The results are discussed from the perspective of the role played by CS in mediating the seasonal rhythms that affect reptilian immunity.